Lubricating devices for sewing machines



Nov. 6, 1956 E. w. JOHNSON ETA!- 2,769,413

LUBRICATING DEVICES FOR SEWING MACHINES Filed March 8, 1954 2 Sheets-Sheet l Fig. l.

INVENTORS. W. d o l v Thomas M. ona so mmss BY and Roberl w. Hewey Nov. 6, 1956 w, JOHNSON ET AL LUBRICATING DEVICES FOR SEWING MACHINES 2 Sheets-Sheet 2 Filed March 8. 1954 Fig. 2.

INVENTORS. Edwin W Johnson, Thomas M. Donaldson and Robert W. Hewey ATTNIZV United States Patent LUBRICAT-ING. DEVICES FOR MAC lNE 4 Claims. (Cl'...112256)' inyentionrelatesto lubrication of sewing machines and; m re p icul y to a m a s. orp op r y b t g the drive gearing of a sewing machine loop taker.

Thelubi c g mean o thepr sent in n n s an ad an ag ous pp c i to the dri e afing6 iat ith; a ver ical s rotary hec f lo t h wi machi eofthe ype employing ho k-s pp r h a a or saddle which is also adapted to carry a bobbin case opener mechanism that is driven in timed relation with the ot ry ho Sewing speeds in excess of 4,000 stitches per. might? are d manded of m de n se g mach n Q As iswe k kno n i t r o lo k-s itch s w n the lnepstaher; on otary book mus e. iv y q evolu i ns for each reciprocation of the needle, so that hook speed demands app oa g ,00 R. P; a not uawmm inyer ical axis. rotary hook m ines- Ihe prob em of r in h driv sca n fo u h hi h.- speed books s mor pro n e in i of h requen tar i an s opp ng inc d nt o norma sewiaa machi e operat n. Mo eo r. a l e y s re dihg s i po e upon he g ar y t b bb n e p n mech nism; which must be driven y h r ta y hd sear dri e- It is an object of this invention to provide a simple and eflicien u rica ys e r the d iv e r ng Qt a sewing, machin pake V It is a further object of this invention to provide a lu ri a ing me ns o th abov ch ra te wher by a c nin ons flo otlu ri i i s r d d ec ly o the Wea n surfaces of thegcar teeth.

It s also an object f h s n en ion. to prov de .a lubricating system for the drive gearing of a sewing machine loop taker in which the. dissipation of lubricant is carefully controlled to prevent lubricant from being thrown by the gearing onto the work or the sewing machine operator.

drawings of a preferred embodiment in which:

'Fig. 1 is a side elevational view of aportion of a sewing machine, partly in vertical sectiop, and having my invention applied thereto;

Pig. 2 is an enlarged end elevational'v'iews-of the sewing machine of Fig. 1 with the machine frame being illustrated in vertical section to expose the rotary hook support or saddle; and V Fig. 3 represents a vertical section through the hook saddle taken substantially along line 33 of Fig. 2.

Referring to Fig. 1, the gear drive for a rotary hook in which the lubricating means of the present invention is embodied is shown as applied to a two-needle lock-stitch sewing machine. The machine comprises a conventional frame including a work-supporting bed 10, a vertical standard 11 rising from the bed and a sewing head 12 supported by said standard and overhanging said bed. Journaled for vertical reciprocation in the sewing head is a ea -ta c 5.6

F P i needlerbar 13 which carries twoneedles, 14-14 spaced apart lengthwiseof the bed. The needle-bar is recipro: cated. in, the usual fashion by suitable mechanism (not shown) carriedm the upper portion of the machine frame. Also journaled vertically in the sewing head is a presserbar 15. which is spring biased downwardly and to which isaffixed a work-engaging resser-foot 16.

Jonrnaled beneath bed 10 in a ball bearing 17- and ee e bu hin s. :8 nd s h 20 whi h i drive a by a belt 21, in one-to-one relation with the needle-bar actuating mechanism in the upper portion of the frame i. e. belt 21 imparts one revolution to bed shaft 20. for each cycle of needle reciprocation. A conventional four-motion, work-feeding mechanism is pro: vided including a feed-dog 22 which is disposed to, work in opposition to the Presser-foot through slots formed in a. throat plate 23. carried on the bed. Motion is imparted to the feed-dog in a manner well known in the art by means of a feed-lift eccentric Z4 and an adjustable feedadvance eccentric 25, both carried by the bed shaft 20.

Cooperating with the spaced needles 14714 in the forof. twospaced lines of lockstitches are two vertical axis rotary hooks 26.2 6 each carried in a support bracket or saddle 27 disposed one at each side of the feed-doghZZ. Each of'the saddles 27 is clamped to a respective one of thebed shaft bushings 18, 19 and each is also secured by means of a fastening screw 28 which is threaded into the underside of the bed. 'Since both of the hook saddles and the driving'connections therein a esiaiila s e t a e r of th Opposite ha d a scription of one will apply to both and will be sufiicient for an understanding of the present invention. 7

Referring moreparticnlarly to Figs. 2 and 3; the hook saddle 27 is formed at one side of the bed shaft 20. with a horizontally extending opening 3% which divides the saddle into vertically spaced portions 29 and 29'. The bottom of the sadddle 2,7 is-recessed and closed by a botcover plate 31 to provide a reservoir 32 from which the rotar y 2 6 is lubricated. The hook 26 is secured for rotation-with a hook-shaft 33 which is journalcdvertically in the saddle 27 in anti-friction bearings 34.,34 one in each of the spaced portions 29, 29' so that the hook shaft spans the horizontal opening 30 of the saddle and depends into the reservoir 32. y

At its lower extremity the hook shaft is formed with a screw pump indicated as 35 which is adapted to force lubricant from the reservoir 32 through a bore in the hook shaft to the hook.

Journaled vertically in the hook saddle in bushings 36 36 is a bobbin case opener shaft 38 which spans the horizontal opening 30 in the saddle and is parallel in the hook shaft 33. At its upper extremity, the bobbin case opener shaft is provided with a crank pin 39 which is embraced by a pitman 40 which in turnis pivotally connected to a bell-crank lever 41 supported atop the hook saddle. The bell-crank lever 41 carries a bobbin case opening finger 42 whic'his adapted upon rotation of .the

bobbin case opener shaft 38 periodically to engage a lug 4 3 extending from a bobbin case 44 about which.,t h ef hook 26 rotates. k Rotation of the bobbin case with the hook is prevented by a rotation-restraining finger 45 projecting from the bobbin case, which finger is confined between spaced stop lugs 46-46 which depend from the throat plate 23. The action of the bobbin case opening finger, as is well known in the art, is to open a gap between the rotation-restraining finger 45 and the stop lugs 4646 for the free passage of the needle thread therebetween during each cycle of stitch formation. I

Both the hook shaft and the bobbin case opener shaft are driven from the bed shaft 20 by means of a helical gear 59 which is made fast to the bed shaft by means of a set screw 51. Secured to the hook shaft 33 by set screws 7 train; c 7 7 To h g 54 is constructed of a porous material,

i 52 and disposed within the horizontal opening 30 of the hook saddle is a helical pinion 53 which meshes with the a 7 gear 50. The pinion 53 is made half the size of the gear 50 so that the hook will partake of two revolutions for each cycle of needle reciprocation.

The'bobbin 'case' opener shaft is driven at half the speed of the hook shaft by means of a gear 54 which is secured to'the opener mesh with the hook driving pinion 53.

' The gear train 50, 53 and 54 is exposed thefgears 53' and 54 being disposed in the horizontal opening '30 in shaft 38 by means of a set scr'ew 55 and'is disposed in the hook saddle so that convenient access may be had to. them to facilitate timingadjustment of the hook and of the bobbin case opener mechanism. These timing ad- I justments may: be made by loosening the set screws -52 and 55 .and angularly adjusting the hook shaft 33 or bobbin case opener shaft '38 with respect to their respective' driving gears 53 an'd'l54. The main driving gear 50 isalso exposed so that access may be had to the set screw 5 1by which the position of the gear 50 may be shifted along the bed shaft 20. Such adjustment is necessary 7 whenever it is desired to shiftthe hook saddle bodily as to'accornmodate a difierent lateral spacing of the needles Since the gearsare exposed and prone to collect lint and dust incident to the operation of the sewing machine, communication of the gears with the lubricant reservoir 32 for the hook is disadvantageous; Accordingly, the

construction of the present invention provides for an independent supply of lubricant to the gear train 50, 53 and 54 V in which the bobbin case opener gear 54 is formed and adapted to. provide a lubricant reservoir for the gear 7 preferably of'a sintered metal product through which it is possible to maintain a flow of lubricant. An annular a recess 56 is forrned in the upper face of gear 54'with the Having thus described the nature of the invention, what 'weclaim hereinis:

1. In a sewing machine, a loop-taker supporting saddle,

an actuating shaft journaledfor rotation in said machine, a driven shaft journaled for rotation in said saddle, a train of gears connecting saidactuating shaft to'said driven shaft, at leastone of said gears' being rotatable about a substantially vertical "axis and beingirormea of aporous material capable of conducting lubricant therethrough, an.

upwardly open lubricant containing recess formedlin said porous gear, and, means in sa i lubricantinto'said recess.

2. In a sewing'machine of the type havin gan actuating shaft and .a loop taker supporting saddle, a pairiofg shafts journaled in said hook saddle, a continuous train fOf gears operatively 'interconnectingtsaid .shafts,;one'of said gears bein constructed of a porous material and being formed outer peripheral 'sidewall'of the recess being preferably undercut as shown at 57in 'Fig'. 3. Lubricant of the proper typefor the gearjtrain may be introduced periodically to a pad or wick 58 disposed in the recess 56 via an oil hole 59. which is formed vertically in theihook saddl e portion 29' and terminates above the'recess 56. 'Under 'centrifugal'action during operation of'the sew ing" machine, lubricantfrom the recess '56 is dispelled radially through the porous gear 54 directly to the. teeth thereof, This lubricant is picked up by the :teeth of the 7 lubricant therethrough, said'porous' gear being disposed hook driving pinion 53 which is in mesh with gear 54 and. V

'is in turn transferred to the teeth of the main driving gear in mesh with the pinion 53. The pinion 53 and .the main driving gear 58 are preferably constructed of conventional nonporous material.

. The porosity of the bobbin case opener gear provides for a nice metering action sothat'uponsupplying lubricant to the recess 56, the flow of the lubricant to the gear teeth continues over:a relatively long periodof time thus supplying" a prolonged flow of lubricant directly to the wearing surfaces of the gear teeth. This metering action of the porous gear 54 is also important since it minimizes objectionable spilling or throwing off of lubricant onto thework being stitched or onto the machine operator.

1 The present 'invention, therefore, provides a simple and economical system' for providing'lubrication in an ideal 'm'anner to the drive gearing of a sewing machine loop taken 1 in one facewith an annular recess defining a lubricant reservoir, and means formed in said hook saddle'for -di- V recting a supply of lubricant into the recessof said porous gear. I e

3. In a sewing machine of the type having an actuating shaft and a loop taker supporting saddle, a pair of shafts carried bysaid hook saddle, at least one of said last men tionedpair'of shafts being journaled insaid hook saddle on a substantially vertical axis, a continuous train 'of meshing gears operatively interconnecting said pair of shafts with said actuatingshaft including a gearof porous material capable of conducting lubricant therethrough being secured for rotation-with said -vertical axi's' shaft,

an annularre'cess' formed in the top side 'of'saidfporous gan and means for directing a supply of lubricant into the recess of said porous gear. a a

4.1m sewing-machineof the type having an actuating shaft," a loop taker supporting saddle extending across said actuating shaft, said" saddle having vertically spaced projections disposed at one side of said' actuating shaft;

a hook shaft and a bobbin case carrier opener shaft being 'journaled vertically insaid projections, a continuous train f of m'eshing gears'operatively interconnecting said shafts including a gear of porous material capable of conducting between the projections of said hook saddle and secured for rotation with one of saidfsh afts journaled' vertically therein, an-annular recessformed in the top side of said porous gear, the: outer peripheral sidewall of said annular recessbeing undercut, and nieans :formed in the hook saddle projection above said porous gear for directing lubricant into said annular recess,

- @Refeninces Cited in the file of this patentt g V UNITED STATES'PATENTS r 1,041,654

7 7 OTHE R REFERENCES 7 p g V -Prod uct Engineering (Arata), August 1944 (pages 561-564 inclusive relied on); t 

